Fuel-oil burner



June 17, 1930. 1 E ,JQHNSQN Er AL FUEL OIL BURNER w Filed March 26, 1928 -2 sheets-sheet 2 /7/ rv-"T Patented 'Jane v17, 1930 UNITED STATES PATENT OFFICE LAWRENCE E. JOHNSON, or umarmen,l Nn ERNEST C. maori, or weer PEABODY, MAssACHUsETTs, AssIcNons To LYNN rnonuc'rs Co., or LYNN, uassncnusmrs,

a CORPORATION or missacmrsmrs .FUEL-ori. nomma application mea Marchas, was. serial No. 2s4,ss 1.RElSSUED i vThe invention has relation to, fuel oil burners, and in particular to f uel oil burners of the type adapted to be employed in connecttion with domestic stoves and ranges to provide heat for cooking and other household purposes. i

Fuel oil burners of various kinds designed for installation in domestic ranges originally made for: the combustion of wood or coal 10 have long been known in the art. Of the various types of such ldevices one'that has entered widely into use comprises a horiaontally disposed circular groeve, or a plurality of grooves arranged concentrically, l5 each groove bein provided with perforated sleeves one of w ich stands upon the outer lip and the other upon the 'inner lip ofl said groove. 'llhe liquid fuel is fed by gravity into the groove or rooves andignitedwith- 2@ out the use of a wic and after ashort period of voperation the metal of which thegrooves are formed becomes heated suiicientlyto vaporize the fuel as fastas it is fed thereto, and 4the resulting vapor rises and burns in the 25 space. between the pair' of sleevesrwith an adm'iizture of adequate atmospheric oxygen through the perforations to produce a very hot blue iame.

One 'limitation of the old construction is 30 that the burner will not operate efliciently with fuel of heavier grade than kerosene, on account of the difficulty. of maintaining a suilicient heat in the metal of`V the grooves, which lie below the flame-level and the level 35 of the products of combustion, to produce sustained vaporization. Kerosene is of hi her cost and poorer` in heat-value than ot el' slightly heavier petroleuln derivatives, and in certain localities is of limited distribution 4 and availability. Another limitation of the old burner is its relatively rapid fouling by the residues of combustion, and the disturbance to the proper operation ofthe flame caused by a relativel small amount, of such residues. Other limitations include the dificulty of cleaning theburners, and the'ditli'- culty of lighting them. i

An important feature of our novel and improved fuel-oil burner comprises the combination with a combustion chamberv and a ling conduits or passages for distributingfuel source of fue1 s uppl of a. 'closed vaporizing chamber 1n which t e fuel i's vaporized and the volatile products allowed to pass on to the.

combustion chamber while the residues are retained. Further features comprise rovi sion for facilitating the removal of suc residues from the vaporizing chamber and the provision of improved means for priming the urner.

The illustrative embodimentof the invention is shown in the accompanying drawings, 1n which Figure 1 is a lan view 'of a pair. of burners embodying the invention, one with the lids in 'place and partly broken away to show the vaporizing chamber, and the other with lids, sleeves, and the removable part of the vaporizing chamber lifted olf to show the arrangement of the base-portion;

F1 2 is a view, in vertical section, ofone comp ete burner, made on line 2--2 ofFi 1; Y Eig. 31s a view, in elevation; and Fig. 4 a bottom view, of the heat-.transmitting memknown type are'shownin the drawin s as are necessary to an understanding of the present invention and its application. The

general arrangement shown is a typical one.

designed to be installed in a domestic stove,

or range as commonly built for the use of coal or wood as fuel, for the purpose of converting it for burning oil. The burners are arranged in pairs as shown in Fi 1, supported in the fire-box by a stan ard (not shown) engaging at 1.- with the web 2 unitmg the two base-portions of the burners.

yThe burners shown have each two vaporl"distributing grooves 3, .4, concentric and v/horizontally disposed, and combined with each other and -with a central cu 5, constitutin .a part of our invention, y suitably distri uted radial tubular ribs 6, 6, 6, form- Iles from the central cup to the inner and outer grooves 3 and 4. Liquid fuel is fed into this novel central cup 5 in suitable. manner, as tlirou h a feed-pipe 7 screwed into a threaded axial ore 8 formed in a boss 9 on the underside ofthe cup 5. Thefuel may be fed into atmospheric oxygen is admittedthrough the many perforations in such manner as to mix with the rising vaporized-fuel, or gas, and roduce a completely combustible mixture urning `with a very hot blue fiame. Lids 12,- circular, and y13,V annular, are applied to the top. of the sleeves to hold them steady and properly spaced apart, the annulus 13 being provided with lugs 14 at appropriate points tofengage the outermost sleeve and hold it in spaced relation. The spaces 15, 15, 15, admit air from below to enter the perforations. The annular yopenin atthe top of the combustion chamber de ed by the inner pair of sleeves 11, 11, and their groove, is made slightly narrower by the outward extension of lid 12 and the inward extension of annulus 13, to insure an adequate supply of vaporized fuel reaching the outer combustion chamber.

In such burners hitherto in use, the oil is customarily admitted in liquid form directly into the grooves, where after the diiiculty experienced in lighting it has been overcome the oil is vaporized by the heat of the metal in which the grooves are formed, derived from the flame propagated in the combustion chamber at all points above the lips of the grooves. This vaporization is a process which leaves behind it at its point of occurrence \.a residue even when the best grades of fuel suitable for this use are employed. This vaporization also occurs in prior forms in the supply ducts, and as this residuel is very hard and tenacious in adhering to the metal, collects rapidly with all fuels except high-grade kerosene and must, in spite of the dliiiculty of so doing, be removed from the grooves and also from the ducts in order to secure efficient combustion, the most satisfactory operation has not been secured from prior devices. V

In accordance with our invention, we provide. a 'separate chamber for the complete vaporization of the fuel oil, to which substantially all the vaporizing and deposit of residue are confined, and from which such deposit may be easily and quickly removed,

and supply the oil in such chamber with a. greater egree of heat, to speed up the production of vapor of a hotter and more inflammable nature, to attain better combustion, and increase the efliciency of the burner.

This vaporizing chamber previously referred to as new 1n the combination of elements is formed within the central cup 5, which preferably has the internal shape of a solid of revolution, herein a cylinder, by the addition of a cover .or top which may eiiciently b e in the shape .of the novel heat-collecting and conductmg member shown separately'in Figs. 3 and 4, which is cup-shaped itself, with a bottom 16 havin a depending rim 17 .to enter the mouth o cup 5 and a flange 18 to Iit gas-tightl but removably upon the lip of cup 5. vThe cylindrical'side-wall 19 is made as high as desired to collect thenecessary amount of heat radiated from the adj acent inward surface ofthe inmost sleeve 11 which is red-hot when in use, and being preferably made of brass this heat flows rapidly throughout the cup and down a plurality of integrally-formed blades or fingers 2O projecting down within the cup from the bottom 16 and into the liquid fuel as it arrives at the burner from the feed-pipe 7 and wellsup in the cup. The heat-conducting member also passes heat to the whole body of metal forming the cup 5, to complete the vaporization. Extending far above the level of the lowest point of flame propagation, the member is at a great advantage over the grooves themselves in the matter of acquiring heat, and through its heat-transmitting characteristic operates so eiiciently that with proper adjustment of the oil-level nothing but dry vapor leaves the cup and passes through the ducts atatmospheric pressure to the grooves 3 and 4. It will be obvious that the original function of thegrooves 3 and 4 has been done away with, and that they simply function as distributing passages for vaporized fuel, and any other method ofv distributing and mixing air with the vaporized fuel may be employed without departing fromthe scope of our invention; but the old structure has been illustrated herein because it operates in combination, and in order to make more emphatic the improvement in the eiiiciency of the burner and its freedom from choking up with residue. A band of wire cloth 21 (Fig. 2), which will act as a strainer for the incoming fuel, may be placed loosely within the vaporizing cup 5 so that it can readily be removed when the cover 19 of the cup is taken 0E t0 permit cleaning. The organization shown and described herein vaporizes its fuel in a special chamber which is easily cleaned and also adequately supplied with heat. Through the novel arrangements provided, the said chamber is amply heated even though located below the level of the tops of the grooves 3, 4, so that the principle of feeding from a source lying below the level of said grooves but above the bottom thereof may be employed, to rodu'ce a device that will not iiood or overildw and create a re hazard. Hitherto this heating of avaporizing chamber,.when provided as a distinct part as herein, involved its location in the path of the flame, or hot products of combustion. In prior devices, to subject the vaporizing cham er to heating'thus effected by convection, it has had to. be lacedA in the path of the risin hot gases, an hence above the grooves, an the safety. features of the oil-level principle could not be attained; or the hot gases were required to be diverted out of their normal upward course, and carried in a circutous route downward to heat a chamber below the level of the tops of said ooves,

with resulting delay in getting the eat to the desired point of appllcation, such as the cooking utensils, etc., placed upon the range, and consequent loss of efficiency. In the improved construction, the roducts of combustion rise vertically and 'rectly, and are applied to the utensil or other object at the moment when their temperature is highest. Further, either burner may be operated inde endently of the other, while oil is fed to oth from the common feedipe, without any need for aseparate shut-oft or each.

lin prior burners of this general type no provision was made for priming the burner preparatory to lighting it, and the procedure of starting up the burner involved turmn on the fuel to How into the grooves, and t en striving to light the fuel therein with a thin torch capable of being inserted between the sleeves into the grooves. In the absence of wicks this has been no simple matter to effeet with fuel'oil and resort has been had to auxiliary burners, rings and pans to receive cohol, gasoline, and like highly inflammable liquids have been poured down as priming between the sleeves to enter the grooves, but not without considerable risk when afterwards ignited as the fuel thus dispensed vfloods many other parts as well as the grooves and can create an explosion hazard in the confinement of the {ire-box of a range. It is not practicable `to remove the sleeves to prime the burner. u

The present invention providesa slmple priming means which is safe and effective in use. The heat-transmitting member is rovided with a central hole 25 through its ottom 16, referably axially disposed. In this hole 25 ts loosely a short rod or plug 26 having a shoulder 27 formed thereon, or formed by an applied washer, to bear a alnst the u per surface of bottom 16 and etermine t e extent of its downward projection into lthe cup 5. This rod 26 when axially located is aligned with the e'nd of the feed-pipe 7. AA

`the u .priming liquid such as gasoline or alcohol,

may be poure into the clip-shaped up r portion of the heat-collecting member aflgr the circular lid 12 has been remove and` ignited to heat the said member and the cup 5 comprising the rest of the va orizing chamber. While this-priming flui'is burning, a certain portion seeps through the hole 25 and flows down the rod to drip 1nto the feed pipe. When the burner is shut-olf after use and allowed to burn itself out, the contraction of the previously warmed fuel oil in the feed-pipe causes it to drop from one to two inches below ducing a lighted s lint into the space between` the sleeves now lled by the rising mixture of vapor and air. Thereafter the burner continues to burn steadily on the regular fuel. The priming fluid is easily directed into the large and accessible cup-shaped ortion o f the heat-transmitting member wit out spilling, and no explosion hazard is created.

A marked advanta e of the burner of our invention, resulting om the described improvements in design and o eration, is that 1t will work with fuels o hi her specific gravity, and of cheaper cost, t an will the burners of like type hitherto in use. This feature adds tothe utility of the burner gives a range of choice of fuels where several grades are available, and enables its use in localities where kerosene is not to be had but heavier hydrocarbons are obtainable. The

per end of the feed-pipe, and the primc heavier fuels are richer in heat units and the eiiicient vaporizing ability of the present burner enables it to handle them and maintain a steady and intensely hot combustion. The increased residues are collected in a place where they will not interfere with prolonged operation and from whence they may be readily removed, whereas the old organizations either cannot be started to operating on heavy hydrocarbons' or, if lighted, then through insuicient vaporizing 1n the grooves to support sustained combustion they lose headway and go out, or speedily clog up with residue and give unsatisfactory service.

Reference has been made to the commercial value of a desi that facilitates cleaning of residue at all tlmes with ease and simplicity. While, in general, the nature of the fuel used is `such that the vapor-conducting conduits 6 lreinain clean during long use, still the c oking of these ducts by deposit of residue therein through poor fuel or improper operconduits 1s thus accessible to a cleanin ation must be guarded against to maintain efficiency of the burner at all times. This is one purpose of the radial, horizontal vapor conduits leading from the vaporizing cham-A ber straight through the inner groove 3'to the outer groove 4. The entire length of thes too inserted from the inner or vopen end. sure that the outer ends of the vapor conduits may adequately be cleaned the diameter' ofthe vaporizing chamber 5 is purposely made at least equa to the length of a conduit 6, 6. This permits a conduit cleaner of ample length to be introduced within the vaporizing chamber and to be manipulated elliciently for cleaning the conduit from end to end whenever necessar While our urner, as illustrated, is of circular form, this being the most satisfactory type to manufacture, the advantages herein set forth will be secured if the principles of operation are utilized with other geometrical forms. c

Thus by our invention'is produced an improved fuel oil burner suited to use in domestic ranges and in other connections, having valuable practical advantages over prior devices ofthe same sort.

The nature and scope of the invention having been indicated and its preferred embodiment having been specifically described, what is claimed as new, is

1. A fuel oil burner embodying a base having a central vaporizing chamber and vapor distributing conduits connected therewith, two annular combustion chambers, one within the other, surrounding said vaporizing chamber and in communication therewith through said conduits, each combustion chamber having a pair of perforated cylindrical walls, and covers comprising a circular and an annular plate, the circular plate resting on the upper edge of the inner wall of the inner combustion chamber and the annular plate resting on the upper edges of the outer wall of the inner combustion chamber and the inner wall of the outer combustion chamber and said annular plate having radial spacing lugs to engage the top edge of the outer wall of the outer combustion chamber.

\ 2. A fuel oil burner comprising, in comblnation with a source of liquid fuel supply, a base having a horizontally arranged endless vapor-distributing groove underlying a oombustion chamber, a cup-shaped vaporlzing chamber, associated with said combustion chamber and derivin heat therefrom to convert liquid fuel within the vaporizing chamber into vapor, having a pipe from the fuel source connected toits bottom from below and said bottom being in a plane below the level of the bottom of said groove, andvaporconducting conduits connecting the bottom of said groove with the `vaporizing chamber, said connection with the vaporizing chamber being throu li the wall thereof at a level substantially a ove the bottom thereof. g

3. An oil burner comprising, in combination with a source of liquid fuel sup ly, a base having a plurality of horizontally arranged concentric lipped vapor-distributing grooves, a pair of spaced perforated walls supported by the lips of each groove to form a combustionchamber ,and a central heating chamber, a cup-shaped vaporizlng chamber within said central heating chamber and connected to said groove by inner horizontal vapor conduits having their bottoms substantially at the level of the bottom of said groove at their outer ends but substantially above the bottom of said vaporizing chamber. at their inner ends, outer horizontal vapor 'conduits between the grooves for connecting one with the other, the bottom of said vaporizing chamber being substantially below the level of the bottoms of said grooves, and a pipe from the fuel source, wholly outside the burner, connected to an opening in said vaporizing chamber. v

4. An oil burner comprising inner and outer concentric combustion chambers each com prising a horizontal bottom vapor groove with vertical walls rising from the edges thereof a cup-shaped vaporizing chamber centralized with respect to said grooves having its bottom at a lower level than the bottoms of said grooves, said vaporizing chamber being connected to said grooves by a plurality of radial tubular members forming vapor conduits communicating with the vaporizing chamber at their inner ends substantially above the level of the bottom of said chamber and communicating with the bottoms of both grooves at their outer ends, and a pipe for supplying liquid fuel to be vaporized connected to the vaporizing chamber below the level of the bottoms of said vapor conduits and outof the path of the products of combustion.

5. In a fuel oil burner, a combustion chaml. ber having an endless, bottom vapor-groove,

a vaporizing chamber adjacent said groove and communicating'with said vapor-groove, afuel supply pipe connected to the bottom of said vaporlzlng chamber, and a cupshaped cover above the vaporizing chamber adapted to be heated by priming fluid burned therein and to conduct heat thus generated to the fuel supplied to the vaporizing chamber.

6. In a fuel oil burner, a combustion chamberhaving an endless, bottom vapor-groove, a4 vaporizing chamber adjacent said groove and communicating with said vapor-groove, a fuel'supply pipe connected to the bottom of said vaporizing chamber, and means above the va orizing chamber for retaining a quantity o highly volatile priming fuel while being consumed and also provided with a small bottom port in alinement with said: supply pipe to permlt dlscharge of priming fuel into the supply pipe for mixture with the ordinary fuel supplied through said pipe.

7. A fuel oil burner embodying an integral base comprising a pair of concentric lipped vapor grooves, afcentral vaporizing chamber and vapor-distributing conduits leading outward from said chamber communicating with both grooves, a pair of spaced perforated Walls supported by the lips of each groove to form a combustion chamber thereabove, the inner Wall forming a central heating chamber Within Which the vaporizlng chamber is located, a solid metal cover closing` the central heating chamber, a cupshaped metal cover closing the vaporizing chamber having its Wall extending` upward Within the central heating. chamber toward the metal cover thereof and in proximity to the surrounding Wall of the inner combustion chamber, and means for supplying; liquid fuel to the vaporizing chamber.

8. A iiuel oil burner embodying a base hav'- ing a central vaporizng chamber from which,

radiate vapor conduits, a heat conducting member closing the upper side of this vaporizing chamber and being removable therefrom to facilitate cleaning the underlying chamber, asurrounding combustion chamber having a groove to which said vapor conduits lead thereby forming a central heating chamber Within which said heat conducting member is located, and a cover on the central heating chamber for absorbing heat from the combustion chamber and reflecting it down- Ward upon the heat conducting member. v

9. lln an oil burner of the type in `which liquid fuel is vaporized and the vapor conducted to' vapor distributing grooves underlying combustion chambers, inner and outer concentric vapor-distributing` grooves, a central vaporizing chamber in the form of a cup having a diameter atl least equal to the length of the vapor-conducting conduits Ytroni said cup to the outer groove, a plurality ot' inner "vapor-conducting conduits extending radially from .the vvail of said cup to the inner groove, and outer vapor-conducting,- conduits connecting the tvvo grooves, said 1nner and outer conduits being in pairs and in tdt) alinernent to form a direct vapor passage from the cup to the outer groove LAWRENCE E. JUHNSN. ERNEST C. USACH. 

